Fruit, Nut, and Beverage Crops July 2014 F_N- 36 Quick Harvest and Postharvest Tips for Better Quality and Longer Postharvest Life Ken Love,1 Nancy Chen,2 and Robert Paull2 1Hawaii Tropical Fruit Growers Association, Captain Cook, Hawai‘i; 2Tropical Plant and Soil Sciences, University of Hawai‘i at Manoa, Honolulu, Hawai‘i Abiu Acerola Pouteria caimito Malpighia emarginata Abiu fruit are harvested when they become bright yellow, Acerola is extremely fragile and must be harvested gently. and the fruit continue to ripen after harvest. Full ripening Generally, acerola should be picked when almost fully occurs in 1 to 5 days after harvest, when the fruit pulp no red. Fruit are often field-packed into clamshell plastic longer has a sticky latex. The translucent flesh becomes containers, no more than two layers deep. A third layer jelly-like, with a pleasant, somewhat caramel-flavored often puts too much weight on the bottom fruit. The pulp. The tough, leathery skin can be easily bruised, but clamshell should be placed in a pre-chilled cooler in the if handled carefully the fruit has a good postharvest life. field to reduce the temperature of the fruit as quickly as The flesh browns quickly after slicing, and the fruit is possible. With rapid cooling, the postharvest life can be usually prepared just before eating. increased from about 4 to 10 days. Fruit with a longer postharvest life are more desirable to grocery stores and chefs and enhance your reputation for high-quality fruit. Atemoya / Cherimoya Annona squamosa x A. cherimola / Annona cherimola It is notoriously difficult to determine the best time to harvest atemoya and its relatives. Generally the skin starts to take on a dull hue and become smoother. But if the trees are producing fruit of irregular sizes and shapes due to inadequate pollination, you may not be able to use the skin becoming smoother as an indicator of ripeness. Judging the subtle changes in the fruit that indicate optimal harvest time takes practice, but the final taste of the fruit makes it well worth the effort. When packaging the fruit, it is preferable to use single-layer trays. Ripening fruit becomes very soft and is crushed if packed in multilayered boxes. Some packers use foam or newspaper in between each fruit, while others pack Abiu, Pouteria caimito each fruit with a foam sleeve. Published by the College of Tropical Agriculture and Human Resources (CTAHR) and issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in co- operation with the U.S. Department of Agriculture, under the Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mānoa, Honolulu, Hawai‘i 96822. Copyright 2011, University of Hawai‘i. For reproduction and use permission, contact the CTAHR Office of Communication Services, [email protected], 808-956-7036. The university is an equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, gender identity and expression, age, religion, color, national origin, ancestry, disability, marital status, arrest and court record, sexual orientation, or status as a covered veteran. Find CTAHR publications at www.ctahr.hawaii.edu/freepubs. UH–CTAHR Harvest and Postharvest Tips for Better Quality and Longer Postharvest Life F_N-36 — July 2014 Avocado black before being harvested. If picked early, the fruit Persea americana will continue to turn black, but flavor and sugar will Knowing when to harvest avocados has plagued never fully develop. Hawai‘i growers for more than a century. The numer- Depending on the needs of a customer, some growers ous named varieties with wide genetic backgrounds will harvest a few fruit to see how long they take to ripen. grown in Hawai‘i, coupled with the many seedling trees If longer than a week, it’s generally too early to harvest descended from unknown parents, has meant different for full flavor. A grower needs to observe the fruit on the criteria have been used. In fact, no single criterion to trees to determine when a particular variety is mature and judge harvest stage is available. Experienced growers ready for picking. Avocados should be packed no more who know their trees rely on a number of ways to tell than 3 layers deep, with similar-sized fruit. when it’s harvest time. For example, with a variety like ‘Sharwil’, a dulling of the skin and darkening of Banana the collar between the fruit and stem is one indicator. Musa spp Occurrence of fruit drop of larger fruit, as long as it’s Bananas can be harvested in a variety of ways and at not due to stress associated with bad weather, is also different stages of development. A recent trend by re- taken into consideration. The skin color of ‘Kahaluu’ sort hotels is to display whole bunches on buffet lines lightens very slightly, and the skin will become dull at so that guests can pick their banana off the bunch. It maturity. Fruit size is not a good indicator, as avoca- is a memorable experience for many. This practice has dos come in many shapes and sizes. When to harvest created the need for growers to be more careful when is also complicated by year-to-year variation, as sizes harvesting so that the sap does not discolor fingers or and ripening times change due to rain and temperature whole hands. Transportation becomes an issue so the patterns. Some varieties with higher oil content like bunch does not get bruised from abrasion, impact, and ‘Kahaluu’, ‘Sharwil’, ‘Malama’, ‘Linda’, and ‘Hass’ tend compression injury. A frame on the back of the truck to be more forgiving than other varieties. Varieties that can be used, with bunches tied down so they do not turn black when mature, like ‘Malama’, need to be fully bang into the floor or roll back and forth while driving. Secured upright boxes with newspaper or foam padding also work. Bananas sold to stores will suffer less damage when the hands are cut and packed in the field, though draining the sap before packing is crucial. Boxes should ideally leave no room for hand movement during handling and transporta- tion. A thin plastic film is used to prevent scuffing injury caused by the fruit rubbing against the cardboard. Again, care should be taken not to let sap discolor the fruit and to avoid all chances of mechanical and abrasion injury. Depending on variety, ripeness indicators can dif- fer greatly. Often the start of loss of fruit angularity is used as a starting point for determining maturity. With Brazilian dwarf, known as Hawaiian apple banana, the sharp lines (angularity) on a finger will begin to smooth and round out and the color will lighten. However, one yellow banana on a bunch or hand is not always an in- dicator of ripeness, as it might be prematurely yellow from insect or mechanical damage. For other varieties, color and skin texture are usually an indicator of when Avocado, Persea americana to harvest. 2 UH–CTAHR Harvest and Postharvest Tips for Better Quality and Longer Postharvest Life F_N-36 — July 2014 Bilimbi especially from the cut peduncle and any injuries on Averrhoa bilimbi the fruit. Latex needs to be allowed to drain from the Bilimbi, like most small fruit, should not be packaged fruit after harvest before washing in water to avoid latex more than 2 or 3 layers deep in a box. Although they can stain. The fruit should be cooled as soon as possible after be used at any stage of development, the fruit will soften harvest. It is graded according to appearance, blemishes, considerably when fully ripe and are easily damaged. maturity, and size. Generally the fruit are harvested when darker green. The fruit should be field-packed in vented clamshells that Carambola (Starfruit) are then placed in coolers in the field, as this can extend Averrhoa carambola shelf life by as much as one week. Bilimbi can also be Carambola can be harvested when the fruit has turned cut and dried for long-term storage; when reconstituted mostly yellow. Wholesalers prefer about 10% to 20% in soup or water, it retains most of its distinctive flavor. green, and the fruit should not have turned from yellow to orange. If too green, the fruit will not contain much Breadfruit sugar. If too orange, the fruit will be soft and have little Artocarpus altilis postharvest life remaining. Before packing, the fruit Mature green fruit are harvested as a starch vegetable, should be carefully inspected for mechanical injury as while some people prefer to eat the ripe, sweet fruit. well as damage from insects and birds. The fruit should Maturity is indicated by larger size, a slight change in always be packed with the stem end down in a box in the skin color, small drops of latex on the rind, and firm a single layer. Sometimes soft foam is put between the flesh texture. The skin segments are also more rounded rows as well as in the bottom of the box. Some packers and smoother on mature fruit. As the fruit starts to place each fruit in an individual foam sleeve for maxi- ripen, the skin changes to a yellowish green and begins mum protection. Carambola should be chilled as soon to soften. Harvested green fruit produce copious latex, as possible after harvest. Bilimbi, Averrhoa bilimbi Breadfruit, Artocarpus altilis 3 UH–CTAHR Harvest and Postharvest Tips for Better Quality and Longer Postharvest Life F_N-36 — July 2014 from the ground if desiccation is not a problem, but more commonly all nuts on one or more bunches, 8 months or more old, are cut and collected at regular intervals throughout the year.